Suicide and seasonality

Association between sleep quality, depressive symptoms, and suicidal ideation in college students

Suicide among college students is a challenging problem globally. Yet, the association between sleep quality, depressive symptoms, and suicidal ideation remains unclear. This study aims to understand if depressive symptoms mediate the relationship between sleep quality and suicide ideation and whether the interaction between depressive symptoms and sleep quality on suicidal ideation is additive. A total of 1182 college students were recruited, and sleep quality, depressive symptoms, and suicidal ideation were assessed using questionnaires. Univariate analysis, logistic regression analysis, linear regression models, and the Sobel test were performed. The results showed that, among college students, poor sleep quality was positively associated with suicidal ideation, and the association was mediated through depressive symptoms. Moreover, there was a significant additive interaction between poor sleep quality and depressive symptoms on suicidal ideation. These findings suggest that, in the process of preventing and treating suicidal ideation in college students with sleep disorders, we should focus on the evaluation and intervention of depressive symptoms and adopt multidisciplinary team interventions for college students with sleep disorders and depression.

The Spatio-Temporal Distribution of Suicide-related Emergency Calls in a European City: Age and Gender Patterns, and Neighborhood Influences

Objective: The aim of this study was to conduct a comprehensive spatio-temporal analysis of suicide-related emergency calls in the city of Valencia (Spain) over a six-year period. To this end we first examined age and gender patterns and, second, the influence of neighborhood characteristics on general and gender-specific spatio-temporal patterns of suicide-related emergency calls. Method: Geocoded data on suicide-related emergency calls between 2017 and 2022 (N = 10,030) were collected from the 112 emergency service in Valencia. Data were aggregated at the census block group level, used as a proxy for neighborhoods, and trimesters were considered as the temporal unit. Two set of analyses were performed: (1) demographic (age and gender) and temporal descriptive analyses and (2) general and gender-specific Bayesian spatio-temporal autoregressive models. Results: Descriptive analyses revealed a higher incidence of suicide-related emergency calls among females and an increase in calls among the 18-23 age group from 2020 onwards. The general spatio-temporal model showed higher levels of suicide-related emergency calls in neighborhoods characterized by lower education levels and population density, and higher residential mobility, aging population, and immigrant concentration. Relevant gender differences were also observed. A seasonal effect was noted, with a peak in calls during spring for females and summer for males. Conclusions: These findings highlight the need for comprehensive mental health targeted interventions and preventive strategies that account for gender-specific disparities, age-related vulnerabilities, and the specific characteristics of neighborhoods.

Increased Suicide Mortality and Reduced Life Expectancy Associated With Ambient Heat Exposure

INTRODUCTION

Ambient heat exposure is a risk factor for suicide in many regions of the world. However, little is known about the extent to which life expectancy has been shortened by heat-related suicide deaths. This study aimed to evaluate the short-term effects of heat on suicide mortality and quantify the reduced life expectancy associated with heat in China.

METHODS

A time-stratified, case-crossover analysis in 2023 was performed during the warm season (May to September) from 2016 to 2020 to assess the short-term association between extreme heat (the 95th percentile of mean temperature) and suicide mortality in Anhui Province, China. A subgroup analysis was performed according to sex, age, marital status, suicide type, and region. The attributable fraction and years of life lost due to heat were calculated, and the heat-related life expectancy loss was estimated.

RESULTS

This study included 9,642 suicide deaths, with an average age of 62.4 years and 58.8% of suicides in males. Suicide risk was associated with an 80.7% increase (95% confidence interval [CI]: 21.4%-68.9%) after exposure to extreme heat (30.6°C) in comparison to daily minimum temperature (7.9°C). Subgroup analysis revealed that heat-related suicide risk was more prominent in the married population than in the unmarried population. Heat was estimated to be associated with 31.7% (95% CI: 18.0%-43.2%) of the suicides, corresponding to 7.0 years of loss in life expectancy for each decedent.

CONCLUSIONS

Heat exposure was associated with an increased risk of suicide and reduced life expectancy. However, further prospective studies are required to confirm this relationship.

Temporal Patterns in Youth Suicide Deaths Reported in the National Violent Death Reporting System

PURPOSE

Suicide is a leading cause of death in children and adolescents. Prevention efforts may benefit from examining temporal patterns and precipitating circumstances of youth suicide deaths. The purpose of this study was to investigate if there are distinct temporal patterns of suicide death for youth.

METHODS

We examined the distributions of suicide deaths across months of the year and days of the week in youth ages 10-18 using data from the National Violent Death Reporting System.

RESULTS

We found that youth suicides peaked during March, April, and October on Monday, Tuesday, and Wednesday. When disaggregated by separate years of age, we discovered unique patterns in 18-year-olds and 10-year-olds. Suicides peaked during July for 18-year-olds and on Saturday for 10-year-olds.

DISCUSSION

These findings suggest a need to examine temporal patterns by separate years of age, as grouping ages together may mask unique trends.

Joint effects of heat-humidity compound events on drowning mortality in Southern China

BACKGROUND

Several previous studies have examined the association of ambient temperature with drowning. However, no study has investigated the effects of heat-humidity compound events on drowning mortality.

METHODS

The drowning mortality data and meteorological data during the five hottest months (May to September) were collected from 46 cities in Southern China (2013-2018 in Guangdong, Hunan and Zhejiang provinces). Distributed lag non-linear model was first conducted to examine the association between heat-humidity compound events and drowning mortality at city level. Then, meta-analysis was employed to pool the city-specific exposure-response associations. Finally, we analysed the additive interaction of heat and humidity on drowning mortality.

RESULTS

Compared with wet-non-hot days, dry-hot days had greater effects (excess rate (ER)=32.34%, 95% CI: 24.64 to 40.50) on drowning mortality than wet-hot days (ER=14.38%, 95%CI: 6.80 to 22.50). During dry-hot days, males (ER=42.40%, 95% CI: 31.92 to 53.72), adolescents aged 0-14 years (ER=45.00%, 95% CI: 21.98 to 72.35) and urban city (ER=36.91%, 95% CI: 23.87 to 51.32) showed higher drowning mortality risk than their counterparts. For wet-hot days, males, adolescents and urban city had higher ERs than their counterparts. Attributable fraction (AF) of drowning attributed to dry-hot days was 23.83% (95% CI: 21.67 to 26.99) which was significantly higher than that for wet-hot days (11.32%, 95% CI: 9.64 to 13.48%). We also observed that high temperature and low humidity had an additive interaction on drowning mortality.

CONCLUSION

We found that dry-hot days had greater drowning mortality risk and burden than wet-hot days, and high temperature and low humidity might have synergy on drowning mortality.

Social and circadian rhythm dysregulation and suicide: A systematic review and meta-analysis

This systematic review of 52 studies provides a quantitative synthesis of the empirical literature on social and circadian rhythm correlates of suicidal thoughts and behaviors (STB). Small-to-medium pooled effect sizes were observed for associations between evening chronotype and STB and suicidal ideation (SI), although the pooled effect size diminished when accounting for publication bias. Three studies employed longitudinal designs and suggested eveningness was predictive of future STB, with a small-to-medium effect size. Social rhythm irregularity was also a significant correlate of STB with pooled effect sizes in the medium range. Overall circadian rhythm disruption was not associated with STB, although certain circadian rhythm metrics, including mean daytime activity, circadian rhythm sleep-wake disorder diagnosis, and actigraphy-assessed amplitude were associated with STB. Pooled effect sizes for these indices were in the medium to large range. There is a need for additional longitudinal research on actigraphy-based circadian parameters and objective markers of circadian phase (i.e., dim-light melatonin onset) to gain a clearer understanding of associations of endogenous circadian function and STB beyond that which can be captured via self-report.

Relationship between biological rhythm dysregulation and suicidal ideation in patients with major depressive disorder

BACKGROUND

Although the disturbance of circadian rhythms represents a significant clinical feature of major depressive disorder (MDD), the relationship between biological rhythm disturbances and the severity of suicidal ideation in individuals with MDD remains unclear. We aimed to explore the characteristics of different biological rhythm dimensions in MDD and their association with the severity of depressive symptoms and suicidal ideation.

METHODS

A total of 50 MDD patients and 50 healthy controls were recruited and their general information was collected. The severity of depressive symptoms was assessed with the 17-item Hamilton Depression Rating Scale (HDRS17). The intensity of suicidal ideation was evaluated with the Beck Scale for Suicide Ideation (BSS). The Chinese version of the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN) scale was utilized to assess the participants' biological rhythm dysregulation. Multiple logistic regression analysis was conducted to explore the relationship between biological rhythm and the risk of MDD. Multiple linear regression analysis was performed in the MDD group to investigate the relationship between different biological rhythm dimensions and suicide ideation.

RESULTS

Significant differences were observed between the MDD group and the control group in total BRIAN score (Z=-5.41, P < 0.001) as well as scores for each dimension. After adjusting for confounding factors, multiple logistic regression analysis revealed a significant association between total BRIAN score and the presence of MDD (OR = 1.20, 95% CI = 1.10-1.29, P < 0.001), as well as between scores in different BRIAN dimensions and the presence of MDD (activity: OR = 1.47, 95% CI = 1.24-1.74, P < 0.001; sleep: OR = 1.52, 95% CI = 1.28-1.79, P < 0.001; social: OR = 1.80, 95% CI = 1.32-2.46, P < 0.001; eating pattern: OR = 1.34, 95% CI = 1.12-1.60, P = 0.001). In patients with MDD, linear regression analysis demonstrated a positive relationship between BSS scores and BRIAN eating pattern scores (β = 0.34, P = 0.022), even after adjusting for demographic factors and the severity of depression.

CONCLUSIONS

Patients with MDD exhibited significantly higher levels of dysregulation in all four biological rhythm dimensions compared to healthy controls and the degree of dysregulation was associated with the severity of depression. More importantly, dysregulation of eating pattern may increase the intensity of suicidal ideation in MDD, thus elevating the risk of suicide.

Evening Chronotype and Suicide: Exploring Neuroinflammation and Psychopathological Dimensions as Possible Bridging Factors-A Narrative Review

A chronotype is generally defined as the variability of the phase angle of entrainment, while the latter reflects the relationship between the timing of a certain rhythm (e.g., the sleep-wake cycle) and the timing of an external temporal cue. Individuals can be placed on a spectrum from "morning types" (M types) to "evening types" (E types). E-chronotype has been proposed as a transdiagnostic risk factor for psychiatric conditions, and it has been associated with psychopathological dimensions. Eveningness seems to be correlated with both suicidal ideation (SI) and suicidal behavior (SB) through several possible mediating factors. Immunological alterations have also been linked to later chronotypes and SI/SB. This narrative review aims to summarize the evidence supporting the possible association between chronotypes and suicide and the eventual mediating role of neuroinflammation and several psychopathological dimensions. A search of the literature (2003-2023) was conducted using various databases: PUBMED, EMBASE, Scopus, UpToDate, PsycINFO, and Cochrane Library. English-language articles were collected and screened for eligibility. Despite the apparent absence of a direct correlation between E-chronotype and suicidality, E-chronotype promotes a chain of effects that could be involved in an increased risk of SB, in which with neuroinflammation possibly plays an intriguing role and some psychopathological dimensions may stand out.

Prevention of suicides associated with global warming: perspectives from early career psychiatrists

Climate change poses significant challenges to global mental health, with potential consequences including increased rates of suicide and mental health disorders. Early Career Psychiatrists (ECPs) play a crucial role in addressing these challenges. The Climate Psychiatry Alliance, a group of psychiatrists dedicated to improving mental health amidst climate change, recognizes the importance of cultivating climate-aware ECPs. Training ECPs to become confident climate-aware clinicians enables them to effectively treat patients experiencing anxiety, depression, and PTSD in the context of climate-related distress. Together with other mental health professionals, ECPs can contribute to efforts by implementing strategies for monitoring and treating mental health problems arising from climate events. Additionally, they can raise awareness about the psychological consequences and risks of suicide associated with climate change. Collaboration among ECPs from various regions is essential in developing community-based approaches and reducing vulnerabilities. ECPs must prioritize supporting vulnerable populations by advocating for increased funding for mental health support and research in affected areas. Long-term solutions to address the mental health impacts of climate change and global warming should be pursued to mitigate future suicidality. Integrating climate considerations into local mental health programs and expanding psychological support services is crucial. By promoting emotional resilience and self-awareness, ECPs can contribute to building a more climate-resilient and mentally healthy society.

Seasonal variations of functional connectivity of human brains

Seasonal variations have long been observed in various aspects of human life. While there is an abundance of research that has characterized seasonality effects in, for example, cognition, mood, and behavior, including studies of underlying biophysical mechanisms, direct measurements of seasonal variations of brain functional activities have not gained wide attention. We have quantified seasonal effects on functional connectivity as derived from MRI scans. A cohort of healthy human subjects was divided into four groups based on the seasons of their scanning dates as documented in the image database of the Human Connectome Project. Sinusoidal functions were used as regressors to determine whether there were significant seasonal variations in measures of brain activities. We began with the analysis of seasonal variations of the fractional amplitudes of low frequency fluctuations of regional functional signals, followed by the seasonal variations of functional connectivity in both global- and network-level. Furthermore, relevant environmental factors, including average temperature and daylength, were found to be significantly associated with brain functional activities, which may explain how the observed seasonal fluctuations arise. Finally, topological properties of the brain functional network also showed significant variations across seasons. All the observations accumulated revealed seasonality effects of human brain activities in a resting-state, which may have important practical implications for neuroimaging research.

Air pollution and suicide in rural and urban America: Evidence from wildfire smoke

Air pollution poses well-established risks to physical health, but little is known about its effects on mental health. We study the relationship between wildfire smoke exposure and suicide risk in the United States in 2007 to 2019 using data on all deaths by suicide and satellite-based measures of wildfire smoke and ambient fine particulate matter (PM2.5) concentrations. We identify the causal effects of wildfire smoke pollution on suicide by relating year-over-year fluctuations in county-level monthly smoke exposure to fluctuations in suicide rates and compare the effects across local areas and demographic groups that differ considerably in their baseline suicide risk. In rural counties, an additional day of smoke increases monthly mean PM2.5 by 0.41 μg/m3 and suicide deaths by 0.11 per million residents, such that a 1-μg/m3 (13%) increase in monthly wildfire-derived fine particulate matter leads to 0.27 additional suicide deaths per million residents (a 2.0% increase). These effects are concentrated among demographic groups with both high baseline suicide risk and high exposure to outdoor air: men, working-age adults, non-Hispanic Whites, and adults with no college education. By contrast, we find no evidence that smoke pollution increases suicide risk among any urban demographic group. This study provides large-scale evidence that air pollution elevates the risk of suicide, disproportionately so among rural populations.

Chronotype is associated with affective temperaments, clinical severity and worse treatment outcomes in bipolar disorders: results from a two-center, cross-sectional study

OBJECTIVE

The present study was aimed at investigating the clinical correlates of evening chronotype in a population of subjects suffering from bipolar disorders (BD).

METHODS

We assessed chronotype using the Morningness-Eveningness Questionnaire. We administered the brief Temperament Evaluation of Memphis, Pisa, and San Diego, the Barratt Impulsiveness Scale, and the Alda Scale to evaluate affective temperaments, impulsiveness, and response to mood stabilisers. We performed bivariate analyses and ran a logistic regression model to analyse clinical variables associated with evening chronotype.

RESULTS

In our sample (n = 178), subjects with an evening chronotype (n = 56, 31.5%) more often suffered from BD type I and reported higher prevalence of seasonality, antidepressant-induced mood switches, psychotic, aggressive, mixed, and anxiety features, and substance use disorders. The number of lifetime suicide attempts and mood episodes was higher in this subgroup. Depressive, cyclothymic, irritable, and anxious temperament scores were higher among evening-chronotype subjects, who also displayed greater levels of impulsiveness and worse treatment response. At the logistic regression, evening chronotype was associated with depressive and irritable temperaments.

CONCLUSIONS

Subjects with evening chronotype display higher clinical severity and worse BD course. Clinicians should evaluate the presence of evening chronotype in BD subjects, especially in those with irritable or depressive temperament.Key pointsEvening chronotype is a frequent clinical feature in subjects suffering from bipolar disorders (BD);Affective temperaments, particularly depressive and irritable, are associated with evening chronotype in BD;Evening chronotype underpins higher severity of the clinical picture in BD, as well as a worse response to mood stabiliser treatment;Circadian preferences should be systematically assessed in subjects suffering from BD, with particular attention to evening preference.

Psychosocial Aspects of Deliberate Physical Suicide Attempts by Children and Adolescents

Suicide is the second most common cause of death among young people in Lithuania. This study aimed to evaluate circumstance, and conditions possibly related to suicide attempt in adolescents. Study was performed at the tertiary Children's Hospital. Medical documentation of the suicide attempts from January 2011 to April 2018 was analyzed. There were 102 cases included in the study: 83.8% female and 16.2% male patients (average age of 15.02 ± 1.9); 40.6% of patients lived in divorced families, 17.7% in orphanages, 4.2% in foster care; 36.4% suffered from parental alcoholism, and 17.2% experienced suicide in close surroundings; 54.1% experienced bullying or violence (26.0%), and 85.4% showed signs of other types of self-harm, girls more often (P < .001). In 52.8% of cases, the attempt was spontaneous, and 34% relapsed. In summary female gender, living in orphanages, and signs of other self-harm were significantly related to suicide attempt.

Using iterative random forest to find geospatial environmental and Sociodemographic predictors of suicide attempts

Introduction

Despite a recent global decrease in suicide rates, death by suicide has increased in the United States. It is therefore imperative to identify the risk factors associated with suicide attempts to combat this growing epidemic. In this study, we aim to identify potential risk factors of suicide attempt using geospatial features in an Artificial intelligence framework.

Methods

We use iterative Random Forest, an explainable artificial intelligence method, to predict suicide attempts using data from the Million Veteran Program. This cohort incorporated 405,540 patients with 391,409 controls and 14,131 attempts. Our predictive model incorporates multiple climatic features at ZIP-code-level geospatial resolution. We additionally consider demographic features from the American Community Survey as well as the number of firearms and alcohol vendors per 10,000 people to assess the contributions of proximal environment, access to means, and restraint decrease to suicide attempts. In total 1,784 features were included in the predictive model.

Results

Our results show that geographic areas with higher concentrations of married males living with spouses are predictive of lower rates of suicide attempts, whereas geographic areas where males are more likely to live alone and to rent housing are predictive of higher rates of suicide attempts. We also identified climatic features that were associated with suicide attempt risk by age group. Additionally, we observed that firearms and alcohol vendors were associated with increased risk for suicide attempts irrespective of the age group examined, but that their effects were small in comparison to the top features.

Discussion

Taken together, our findings highlight the importance of social determinants and environmental factors in understanding suicide risk among veterans.

Differences of chronological seasonality in drug overdose

OBJECTIVE

To investigate the association between seasonality and intentional drug overdose (IDO), a commonly seen method of self-harm in daily emergency medicine practice.

METHODS

Cases of IDO were retrospectively selected using the International Classification of Diseases (ICD)-10 coding system (codes T36-T50), in patients who attended the Emergency Department of MacKay Memorial Hospital between January 2018 and August 2019. Data regarding age, sex, arrival time, marital status, vital signs, comorbidities, psychiatric history, social conflicts, substance of overdose, and length of hospital stay by season, were analysed using Student's t-test and χ2-test.

RESULTS

Of all included cases (n = 196), IDO occurred most frequently in spring (32.1%), particularly in male patients (28/49 male cases). First-time IDO occurred most frequently in spring (51/133 first-time cases) and most spring cases were first-time IDO (51/63 spring cases). Repeat IDO occurred most frequently in autumn (20/63 repeat cases). Female conflict with father and/or boyfriend, and personality disorder in patients who overdosed, showed seasonality with a spring peak. Hospital admission rate was highest in winter (10/45 winter cases [22.2%]).

CONCLUSION

Episodes of IDO exhibited seasonality, with a spring peak, particularly for male patients, female patients in conflict with father and/or boyfriend, and those with personality disorder. Clinicians should pay close attention to the abovementioned patient groups.

A Systematic Review on the Impact of Seasonality on Severe Mental Illness Admissions: Does Seasonal Variation Affect Coercion?

Coercion in psychiatry is associated mainly with involuntary admissions. The purpose of this study was to investigate the associations between hospital admissions of patients suffering from affective and schizophrenic disorders and seasonality. A systematic literature search using PubMed, Scopus and Google Scholar was conducted, including studies with affective and schizophrenia disorder admissions, published from October 1992 to August 2020. A total of 31 studies were included in the review. Four broad severe mental illness admission categories were identified regarding seasonality: affective disorders, schizophrenia disorders, involuntary admission affective disorders and involuntary admission schizophrenia disorders. There was clear and strong evidence for spring and summer peaks for severe mental illness admissions; data provided for age, gender and involuntary admissions was limited. Seasonality may have a significant effect on the onset and exacerbation of psychopathology of severe mental illness and should be considered as a risk factor in psychiatric admissions, violence and the risk of mental health coercion. A better understanding of the impact of seasonality on severe mental illness will help professionals to provide the best practices in mental health services in order to reduce and prevent psychiatric hospitalizations (especially involuntary admissions) resulting in further coercive measures.

Attempted Suicide by Burning: A Cross-sectional Analysis at a Regional Burn Center in Germany

Attempted suicide by self-immolation or burning constitutes an uncommon form of attempted suicide in high income countries, presenting substantial challenges to burn units. The aim of this study was to analyze the epidemiologic characteristics and outcomes in intensive care burn patients treated for attempted suicide by burning. For this purpose, we examined intensive care burn patients admitted to a single major burn unit between March 2007 and December 2020. Demographic, clinical, epidemiological, and mortality data were collected and analyzed. Major psychiatric comorbidities were evaluated according to ICD-9 and ICD-10 classifications. A total of 1325 intensive care unit burn patients were included. Suicide by burning was attempted in 45 cases (3.4%). Attempted suicide victims presented with significantly higher burn severity, reflected by higher abbreviated burn severity index scores, and larger TBSA affected. Burned TBSA ≥30% and inhalation injuries were observed more frequently in suicidal patients. These patients also experienced prolonged hospital and intensive care unit length of stay, required surgical interventions and mechanical ventilation more frequently, and had significantly longer periods on ventilation, causing an overall higher mortality rate (24.4%). Psychiatric comorbidities were present in 75.6% of patients who attempted suicide. Despite the low prevalence, burn severity and mortality are considerably high in patients who attempted suicide by burning, presenting a significant challenge for healthcare providers. The majority of patients had a history of psychiatric disorder, highlighting the importance of identifying patients at high-risk who may profit from increased psychiatric intervention.

Potential links between brown adipose tissue, circadian dysregulation, and suicide risk

Circadian desynchronizations are associated with psychiatric disorders as well as with higher suicidal risk. Brown adipose tissue (BAT) is important in the regulation of body temperature and contributes to the homeostasis of the metabolic, cardiovascular, skeletal muscle or central nervous system. BAT is under neuronal, hormonal and immune control and secrets batokines: i.e., autocrine, paracrine and endocrine active substances. Moreover, BAT is involved in circadian system. Light, ambient temperature as well as exogen substances interact with BAT. Thus, a dysregulation of BAT can indirectly worsen psychiatric conditions and the risk of suicide, as one of previously suggested explanations for the seasonality of suicide rate. Furthermore, overactivation of BAT is associated with lower body weight and lower level of blood lipids. Reduced body mass index (BMI) or decrease in BMI respectively, as well as lower triglyceride concentrations were found to correlate with higher risk of suicide, however the findings are inconclusive. Hyperactivation or dysregulation of BAT in relation to the circadian system as a possible common factor is discussed. Interestingly, substances with proven efficacy in reducing suicidal risk, like clozapine or lithium, interact with BAT. The effects of clozapine on fat tissue are stronger and might differ qualitatively from other antipsychotics; however, the significance remains unclear. We suggest that BAT is involved in the brain/environment homeostasis and deserves attention from a psychiatric point of view. Better understanding of circadian disruptions and its mechanisms can contribute to personalized diagnostic and therapy as well as better assessment of suicide risk.

Spatial and temporal trends and risk factors for intentional carbon monoxide poisoning hospitalizations in England between 2002 and 2016

INTRODUCTION

Suicide and mental health disorders are a recognized increasing public concern. Most suicide prevention rely on evidence from mortality data, although suicide attempts are a better predictor for completed suicides. Understanding spatio-temporal patterns and demographic profiles of people at risk can improve suicide prevention schemes, including for carbon monoxide (CO) poisoning, a common method for gas-related suicides.

OBJECTIVE

Describe spatio-temporal patterns of intentional CO poisoning hospitalization rates in England between 2002 and 2016, and identify population sub-groups at risk.

METHODS

We used NHS Digital's Hospital Episode Statistics (HES) routinely collected data on hospital admissions for intentional CO poisoning. We estimated age-standardised rates (ASR) by year, gender and residential small-area characteristics, including rural/urban, deprivation and ethnic composition. Temporal trends were assessed through linear regression and joinpoint regression analysis. Regional differences were explored.

RESULTS

On average, we identified 178 hospital admissions for intentional CO poisoning per year. The ASR decreased substantially over the study period, particularly among males (average annual percent change of -7.8 % (95 % CI: -11.0; -4.6)), in comparison to 3.9 % (95%CI, -6.4; -1.4) among females. Most admissions (81 %) occurred in males. White men aged 35-44 years were particularly at risk. The ASR in London (0.08/100,000) was almost six times lower than in the South-West (0.47/100,000).

CONCLUSIONS

This study provides novel insights into attempted suicides by intentional CO poisoning. Further prevention interventions, targeting sub-groups at risk (i.e. white men in their 30s/40s), need to be developed and implemented to reduce the burden of suicides and of CO poisoning.

Relationship of emergency department visits for suicide attempts with meteorological and air pollution conditions

BACKGROUND

Environmental factors such as meteorological and air pollution conditions have been identified as risk factors for suicide. This study aimed to clarify the relationship of the number of visits to the emergency department for suicide attempts with meteorological and air pollution conditions.

METHODS

This cross-sectional study included patients who attempted suicide and were transported to Yokohama City University Medical Center from April 2005 to March 2022. The meteorological conditions recorded at the time of transport included mean atmospheric pressure, mean temperature, maximum temperature, minimum temperature, mean humidity, wind speed, and sunshine hours, and the air pollution conditions included SO₂ (ppm), NO (ppm), NO₂ (ppm), NOX (ppm), OX (ppm), CH₄ (ppmC), NMHC (ppmC), THC (ppmC), SPM (μg/m³), and PM2.5 (μg/m³). Poisson regression analysis was used to examine the association between the number of suicide attempts and the meteorological and air pollution conditions. Subgroup analyses were conducted by classifying the subjects according to the means of suicide attempt; comparisons were performed using t-tests.

RESULTS

The study included 1737 patients. Multivariate Poisson regression analyses revealed a significant positive relationship between the number of suicide attempts and SO₂ levels and a significant negative relationship between the number of suicide attempts and NO levels. When subjects were divided by means of suicide attempt, different relationships with meteorological and air pollution conditions were observed.

CONCLUSION

Meteorological and air pollution conditions are environmental factors that can enable a more detailed understanding of suicide behavior according to the means of suicide attempts.

Minimum wages and health: evidence from European countries

This study investigates the effects of minimum wage on health, well-being, and income security in European countries. The empirical strategy consists of exploiting variations in the minimum wage across European countries over time. We show that minimum wage increases improve individuals' self-reported health and income security. Minimum wage increases also improve life satisfaction and happiness. The effects are largest among women, employed individuals, married individuals, and those with less than a secondary education. Our results are robust to several robustness checks and consistent with existing evidence on the relationship between minimum wage and health.

Seasonality and the female happiness paradox

Most studies tracking wellbeing do not collect data across all the months in a year. This leads to error in estimating gender differences in wellbeing for three reasons. First, there are seasonal patterns in wellbeing (particularly life satisfaction and happiness) which are gendered, so failure to account for those confounds estimates of gender differences over time. Second, studies fielded in discrete parts of the year cannot extrapolate to gender differences in other parts of the year. Making inferences about trends over time is particularly problematic when a survey changes its field survey dates across years. Third, without monthly data, surveys miss big shifts in wellbeing that occur for short periods. This is a problem because women's wellbeing is more variable over short periods of time than men's wellbeing. It also bounces back faster. We show that simply splitting the data by months in a happiness equation generates a positive male coefficient in one subset of months from September to January and a negative coefficient in months February to August. Such a split has no impact on the male coefficients in an anxiety equation. Months matter.

The role of meteorological factors in suicide mortality in Wuhu, a humid city along the Yangtze River in Eastern China

As the climate continues to change, suicide is becoming more frequent. In this study, absolute humidity (AH) was included for the first time and Wuhu, a typical subtropical city along the Yangtze River, was taken as the research object to explore the impact of suicide death risk on meteorological factors. The daily meteorological factors and suicide mortality data of Wuhu city from 2014 to 2020 were collected. Guided by structural equation model (SEM), a time series analysis method combining distributed lag nonlinear model (DLNM) and generalized additive model (GAM) was adopted. To investigate the correlation among different populations, we stratified age and gender at different meteorological levels. A total of 1259 suicide deaths were collected in Wuhu. The results indicated that exceedingly low and low levels of AH short-term exposure increased suicide mortality, with the maximum effect occurring at lag 14 for both levels of exposure, when the relative risk (RR) was 1.131 (95% CI: 1.030, 1.242) and 1.065 (95% CI: 1.006, 1.127), respectively. Exposure to exceedingly high and exceedingly low levels of temperature mean (T mean) also increased suicide mortality, with maximum RR values of 1.132 (lag 14, 95% CI: 1.015, 1.263) and 1.203 (lag 0, 95% CI: 1.079, 1.340), sequentially. As for diurnal temperature range (DTR), low-level exposure decreased the risk of suicide, while high-level exposure increased this risk, with RR values of 0.955 (lag 0, 95% CI: 0.920, 0.991, minimum) and 1.060 (lag 0, 95% CI: 1.018, 1.104, maximum), sequentially. Stratified analysis showed that AH and DTR increased the suicide death risk in male and elderly people, while the risk effect of T mean have no effect on young people only. In summary, male and elderly people appear to be more vulnerable to adverse weather effects.

Seasonal and Temporal Patterns of Homicides and Suicides in Cali and Manizales, Colombia: A Times-Series Analysis 2008-2015

OBJECTIVE

To identify seasonal and temporal variations in daily incidence of homicides and suicides in Cali and Manizales, Colombia during 2008-2015.

MATERIALS AND METHODS

An ecological time series study was performed using negative binomial regression models for daily incidence of homicides and suicides; analyses were controlled for yearly trends and temporal autocorrelations.

RESULTS

Saturdays, Sundays, December holidays as well as New Year and New Year's Eve were associated with an increased risk of homicides in both cities. Suicide risk increased during December holidays and New Year in both cities. In addition, the suicide risk increased on paydays, Saturdays, Sundays, and Mondays in Cali, and it decreased during the Holy Week holidays in Manizales. December patterns of suicides and homicides are the opposite in each city, and between cities.

CONCLUSIONS

The incidences of homicides and suicides are not homogeneous over time. These patterns can be explained partially by alcohol consumption and changes in people's routine activities which may modify exposure to violent circumstances.

Effects of the COVID-19 pandemic on suicide attempts in a rural region in Germany, a 5-year observational study

BACKGROUND

The COVID-19 pandemic and public life restrictions may have a negative impact on people's mental health. Therefore, we analyzed whether this condition affected the occurrence of suicide attempts (SA) over 20 months during the pandemic period.

METHODS

We included patient records according to DSM-5 criteria for suicidal behavior disorders (n = 825) between Jan 1, 2017, and Dec 31, 2021. We applied interrupted time-series Poisson regression models to investigate the effect of the pandemic on SA occurrence, time trends, and seasonal patterns in the whole group of patients as well as stratified by age and gender.

RESULTS

There was no significant effect of the pandemic on the occurrence of SA in the overall group. However, we observed a significant impact of the pandemic on the seasonal pattern of SA, also the variance differed significantly (pre-pandemic mean ± variance: 13.33 ± 15.75, pandemic: mean ± variance: 13.86 ± 7.26), indicating less periodic variation in SA during the pandemic. Male patients and young adults mainly contributed to this overall effect. Subgroup analysis revealed a significant difference in SA trends during the pandemic in older adults (>55 years) compared with younger adults (18-35 years); SA numbers increased in older adults and decreased in younger adults as the pandemic progressed.

LIMITATIONS

A few patients may have received initial care in an emergency department after SA without being referred to psychiatry.

CONCLUSIONS

In general, the COVID-19 pandemic and related measures did not significantly affect the occurrence of SA but did significantly affect the dynamics. In addition, the pandemic appeared to affect suicidal behavior differently across age groups as it progressed. Particularly for the older adult group, negative long-term effects of the pandemic on suicidal behavior can be derived from the present results, indicating the need to strengthen suicide prevention for the elderly.

Mechanisms by which adverse childhood experiences, other traumas and PTSD influence the health and well-being of individuals with eating disorders throughout the life span

BACKGROUND

Multiple published sources from around the world have confirmed an association between an array of adverse childhood experiences (ACEs) and other traumatic events with eating disorders (EDs) and related adverse outcomes, including higher morbidity and mortality.

METHODS

In keeping with this Special Issue's goals, this narrative review focuses on the ACEs pyramid and its purported mechanisms through which child maltreatment and other forms of violence toward human beings influence the health and well-being of individuals who develop EDs throughout the life span. Relevant literature on posttraumatic stress disorder (PTSD) is highlighted when applicable.

RESULTS

At every level of the pyramid, it is shown that EDs interact with each of these proclaimed escalating mechanisms in a bidirectional manner that contributes to the predisposition, precipitation and perpetuation of EDs and related medical and psychiatric comorbidities, which then predispose to early death. The levels and their interactions that are discussed include the contribution of generational embodiment (genetics) and historical trauma (epigenetics), social conditions and local context, the ACEs and other traumas themselves, the resultant disrupted neurodevelopment, subsequent social, emotional and cognitive impairment, the adoption of health risk behaviors, and the development of disease, disability and social problems, all resulting in premature mortality by means of fatal complications and/or suicide.

CONCLUSIONS

The implications of these cascading, evolving, and intertwined perspectives have important implications for the assessment and treatment of EDs using trauma-informed care and trauma-focused integrated treatment approaches. This overview offers multiple opportunities at every level for the palliation and prevention of EDs and other associated trauma-related conditions, including PTSD.

Türkiye'nin batı bölgesinde bir şehirde COVID-19 pandemisi öncesi ve sırasında intihar eğilimlerinin karşılaştırılması

Purpose: This study aims to compare the completed suicides in the early period of the COVID-19 pandemic with the completed suicides in the same time interval immediately before the pandemic in the Manisa Province of Turkey and to investigate whether there are pandemic-specific completed suicide trends. Materials and Methods: The study sample consisted of 162 completed suicides that occurred between January 2019 - February 2020 (pre-pandemic period) and March 2020 - June 2021 (pandemic period) in Manisa Province. Completed suicides were compared in terms of sociodemographic and clinical characteristics. Results: The number of completed suicides before and during the pandemic was 84 and 78, respectively. There was no statistically significant difference between the pre-pandemic and pandemic periods in the number of completed suicides. In terms of sociodemographic characteristics, marital status, contrary to gender, age, employment status, and educational level, caused a significant difference in the number of suicides before and during the pandemic period. Additionally, the season when the completed suicide occurred and the type of place of residence of the individuals with completed suicide, caused a significant difference in the number of suicides Conclusion: The study's findings indicated that the pandemic period was not a factor in general in completed suicides. Specifically, however, it is noteworthy that suicide by hanging was more common during the pandemic period, in the spring season, among individuals who were married, employed, resided in urban areas, had a low educational level, and had a history of psychiatric diseases such as mood disorders.

The impact of daylight on suicide rates

Since Durkheim and Morselli found a spring peak in suicides in the late 19th century, researchers have presented possible explanations, including daylight variation, for this seasonal pattern. Our identification strategy exploits the idiosyncratic variation in daylight within Norwegian regions, arising from the country's substantial latitudinal range. We use full population data for a period of 45 years in a pre-registered research design. We find a small and non-significant relationship: One extra hour of daylight increases the suicide rate by merely 0.75 % (95 % CI: -0.4 % to 1.9 %).

An Exploratory Analysis of Fifteen Years Suicide Trends Using Population-Level Data From Croatian Committed Suicides Registry

Objectives

The provide a descriptive analysis of the available population-level aggregated data on committed suicides in the Republic of Croatia, in the 2004-2018 period, showing emerging trends in suicide incidence focusing on sex/age/geographical distribution of suicides and the primary and secondary causes of suicide mortality, as well as making comparisons with similar neighboring neighboring countries.

Methods

The aggregated suicide data were obtained from the Croatian Committed Suicides Registry, a national registry maintained by the public health authority. The raw data extract was organized into tables according to several variables (age, sex, place of birth, place of residence, and cause of death). Simple descriptive statistics were performed on the structured data.

Results

Despite being among the highest in the world and EU, the number of committed suicides in Croatia is in decline since 2004. A higher number of suicides by males was observed when compared to females. Most of the suicides occur during spring and summer. The wealthier, northern continental region of the country had the highest average rate of committed suicides per 1,00,000 population, contrary to some of the findings in the published literature associating economic instability with suicide. The most common way to commit suicide for both sexes in all age groups is self-harm by hanging, strangulation and suffocation. Suicide by firearm and explosive devices discharge remains higher than the global average.

Conclusions

Despite its steadily declining incidence rates in the past 20 years, suicides remain a major public health challenge in Croatia. Results may bolster the Ugro-Finnish suicide hypothesis, linking higher suicide rates to regions with populations of Hungarian descent.

Revisiting the relationship between economic uncertainty and suicide: An alternative approach

Previous research provides evidence that economic uncertainty is powerful enough to precipitate suicide. This study examines whether the relationship between economic uncertainty and suicide in the US is (i) context dependent and (ii) asymmetric. To answer these questions, we link US monthly total- age- and gender-specific suicide rates to the US Economic Policy Uncertainty index between 1999 and 2019, controlling for month fixed effects, year fixed effects and unemployment rates. We find that the relationship between economic uncertainty and the suicide rates of males in their mid-career (aged 25-54) and late career (aged 55-64) is context dependent. Our results show that absolute monthly changes in economic uncertainty have no effect on suicide rates of males aged 25-54 and 55-64, whereas when these changes are unexpected - departing from the economic uncertainty regime during which they occur - they precipitate the suicide of these age- and gender-specific groups. Additionally, our findings provide evidence of the presence of negativity bias in these relationships. We show that extreme unexpected increases in economic uncertainty induce suicide of males aged 25-54 and 55-64, while extreme unexpected decreases in economic uncertainty do not significantly decrease suicide rates of these age- and gender-specific groups. Females, with the exception of those aged 65 plus, are perceived to be predominantly insulated from changes in economic uncertainty. Our results suggest that females aged 65 plus are particularly affected by extreme unexpected increases in economic uncertainty, suggesting that the relationship for females aged 65 plus is context dependent and exhibits negativity bias.

Climate rather than economic variables might have caused increase in US homicide but not suicide rates during the Great Depression

BACKGROUND

It is widely believed that during the Great Depression (1929-1933) there was a rise in suicidal rates which was causally related to the increase in unemployment. There are no studies on the effect the Great Depression had on homicidal rates METHODS: The data concerning suicide, homicide, economic and climatic variables for the years 1900-1940 for the whole of the US were gathered from the US Center for Disease Control, the Maddison Project, the National Bureau of Economic Research and the National Climatic Data Center. Time Series Analysis was performed.

RESULTS

The results are inconclusive on the role of economic factors but preclude any role of climate on suicidal rates during the years 1900-1940 in the US. Suicidal rates might have a 24-years periodicity, however much longer time series are needed to confirm this. On the contrary they strongly suggest an effect of higher temperatures on homicidal rates after 1922.

CONCLUSIONS

The results of the current study suggest a direct and clear effect of climate (higher temperatures) on the increasing homicidal rates in the US after 1922 but failed to establish a causal relationship between suicide rates and economic or climate variables. These should be considered together with increasing concerns on the possible effect of climate change on mental health.

Association between COVID-19 pandemic and the suicide rates in Nepal

BACKGROUND

Past works have linked the COVID-19 pandemic and subsequent public health responses such as isolation, quarantine, and lockdown to increased anxiety, sleep disorders, depressive symptoms, and suicidal ideation. Only a few studies, mostly carried out in high-income countries, have investigated the association between the pandemic and suicide rate. We seek to investigate the changes in the monthly suicide rates during the COVID-19 pandemic in Nepal, compared to the pre-pandemic suicide rates.

METHODS AND FINDINGS

This is a retrospective study investigating the changes in suicide rates in Nepal during the COVID-19 pandemic period (April 2020 to June 2021), compared to the pre-pandemic period (July 2017 to March 2020), adjusted for seasonality and long-term trend in the suicide rate. We performed analysis for the entire country as well as sub-sample analyses stratified by gender and provinces. A total of 24350 suicides deaths during four years of the study window were analyzed. We found an overall increase in the monthly suicide rate in Nepal with an average increase of 0.28 (CI: 0.12,0.45) suicide per 100,000 during the pandemic months. The increase in suicide rate was significant both among males (increase in rate = 0.26, CI: 0.02,0.50) and females (increase in rate = 0.30, CI: 0.18,0.43). The most striking increments in suicide rates were observed in June, July, and August 2020. The pattern of increased suicide rates faded away early on among males, but the effect was sustained for a longer duration among females. Sudurpaschim and Karnali provinces had the highest increase in suicide rates associated with the COVID-19 pandemic.

CONCLUSIONS

The COVID-19 pandemic is associated with an increased suicide rate in Nepal. The findings may inform policymakers in designing appropriate public health responses to the pandemic that are considerate of the potential impact on mental health and suicide.

Effects of catastrophic financial loss on suicide risk: evidence from Korean stock market crash in October 2008

PURPOSE

The negative effect of catastrophic financial loss on suicide risk is widely perceived but hardly studied in-depth because of various difficulties in designing studies. We empirically investigated the effect utilizing the stock market crash event in October 2008 in South Korea.

METHODS

We extracted stock market investor data from Korea Exchanges, and mortality data from Microdata Integrated Service of individuals aged 30-60 years. We calculated age-standardized monthly suicide rate per 100,000 persons according to sex and age, and developed intervention analysis with multiplicative seasonal ARIMA model to isolate the effect of the stock market crash on suicide rate.

RESULTS

More than 11% of people aged 30-60 years were directly investing in stocks during stock market crash. In October 2008, both KOSPI and KOSDAQ indexes dropped by 22.67% and 30.14%, respectively. In November 2008, the suicide rate in males 30-60 years increased by > 40% compared to the expected levels if there had been no market crash, and in females aged 30-40 and 40-50 years, it increased by 101.84% and 74.81%, respectively. The effect appeared to persist in males, whereas it degenerated with time in females during our sampling period. Suicide was more pronounced in younger age groups and females.

CONCLUSION

In this first in-depth study, the effect of catastrophic financial loss negatively affects suicide risk for an extended period, indicating health and financial authorities should provide a long-term financial and psychological support for people with extreme financial loss.

Effects of vitamin D-related gene polymorphisms on attempted suicide

OBJECTIVE

Emerging evidence suggests that vitamin D might protect from attempted suicide. The study aimed to investigate the associations between single-nucleotide polymorphisms (SNPs) related to vitamin D levels identified in a large genome-wide association study and attempted suicide in rural China.

METHODS

This 1:1 matched case-control study included altogether 510 suicide attempters and 510 community controls. Genotypes of four target SNPs (DHCR7-rs12785878, CYP2R1-rs10741657, GC-rs2282679, and CYP24A1-rs6013897) were determined, and a genetic risk score (GRS) was constructed to evaluate the combined effect of them. Demographic and psychological information was acquired through face-to-face interviews.

RESULTS

The A allele of CYP24A1-rs6013897 was significantly associated with attempted suicide (OR = 1.27, 95% CI, 1.03-1.58, P = 0.029), even after adjusting for demographic and psychological confounders (adjusted OR = 1.53, 95% CI, 1.01-2.30, P = 0.043). The GRS analyses revealed a significantly higher risk of attempted suicide with a greater number of low vitamin D alleles (adjusted OR = 1.33, 95% CI, 1.13-1.58, P < 0.001). Subgroup analyses stratified by sex indicated that the genetic associations were only significant among males with adjusted ORs of 3.77 (95% CI, 1.56-9.10) for the A allele of rs6013897 and 2.04 (95% CI, 1.32-3.17) for GRS.

CONCLUSIONS

Our findings identity CYP24A1-rs6013897 as a potential biomarker for attempted suicide and indicate that a genetic predisposition to lower vitamin D levels may contribute to attempted suicide. It suggests the possibility that vitamin D may have the preventive potential for attempted suicide.

Increased C-reactive protein concentration and suicidal behavior in people with psychiatric disorders: A systematic review and meta-analysis

OBJECTIVE

Suicide is a leading cause of death worldwide. Identifying factors associated with suicidality (suicidal ideation [SI]/suicidal behavior) could increase our understanding of the pathophysiological underpinnings of suicide and improve its prevention.

METHODS

We conducted a systematic review (PubMed/PsycInfo/Cochrane databases, up to September 2020) and random-effect meta-analysis including observational studies comparing peripheral C-reactive protein (CRP) levels in suicidal versus non-suicidal patients affected by any psychiatric disorder and healthy controls (HC). Primary outcome was the CRP standardized mean difference (SMD) between patients with high suicidality versus those with absent or low suicidality. Secondary outcomes were SMD of CRP levels between those with suicide attempt versus no suicide attempt, as well as between those with (high) versus low or absent SI. Quality of included studies was measured with Newcastle-Ottawa scale.

RESULTS

Out of initial 550 references, 21 observational studies involving 7682 subjects (7445 with mood disorders or first-episode psychosis, 237 HC) were included. A significant association of CRP levels with suicidality (SMD 0.688, 95% CI 0.476-0.9, p < 0.001) emerged. CRP levels were higher in individuals with high SI (SMD 1.145, 95% CI 0.273-2.018, p = 0.010) and in those with suicide attempt (SMD 0.549, 95%CI 0.363-0.735, p < 0.001) than non-suicidal individuals (either patients or HC). Main analyses were confirmed in sensitivity analysis (removing HC), and after adjusting for publication bias. The cross-sectional design of included studies, and the high heterogeneity of diagnosis and treatment limit the generalizability of these results. Median quality of included studies was high.

CONCLUSION

CRP is associated with higher suicidality in patients with mental disorders. Large cohort studies longitudinally monitoring CRP levels are needed to explore its longitudinal association with suicidality.

Patterns of suicide deaths in Hungary between 1995 and 2017

Hungary has had one of the highest suicide mortality rates in the world for decades. Investigating seasonality of suicide deaths is essential as its findings could be key elements in the prevention. In our study we have analyzed the seasonal effect in suicide mortality in relation to possible risk factors in Hungary during 1995–2017.

Data on the numbers of suicide deaths were obtained from a published online database. Negative binomial regression was employed to investigate the effect of possible risk factors and seasonal and annual trends in suicide rates. The seasonal effect was further investigated, adding a significant risk factor from the “initial” negative binomial regression.

The suicide risk was significantly (p < 0.001) higher in men than in women (incidence rate ratio: 3.48), and it increased with age and decreased with education level. Marriage was a protective factor against suicide. Annual suicide mortality declined significantly (p < 0.001 for trend) from 36.7 (95% confidence interval: 35.5–37.9) to 16.5 (15.7–17.3) per 100,000 persons per year during the study period. Significant seasonality was found in suicide rates with a peak in late June. Similar peaks were observed at each level of each risk factor. There were differences in peaks by suicide method. The peak of non-violent suicides was in early June; suicides committed by violent methods peaked half a month later.

This study suggests that there was a significant seasonal effect on suicide deaths between 1995 and 2017, which remained significant even in the presence of each risk factor. To our knowledge, this has been the first study to investigate the seasonal pattern so extensively in Hungary. Our findings confirm that the environmental effects are involved in the etiology of suicide mortality.

•

Significant seasonality was found in suicide rates with a peak in late June.

•

Seasonal effect remained almost unchanged after adjusting sociodemographic factors.

•

There were differences in seasonal peaks by suicide method.

•

Environmental effects are involved in the etiology of suicide mortality.

Variations in seasonal solar insolation are associated with a history of suicide attempts in bipolar I disorder

Background

Bipolar disorder is associated with circadian disruption and a high risk of suicidal behavior. In a previous exploratory study of patients with bipolar I disorder, we found that a history of suicide attempts was associated with differences between winter and summer levels of solar insolation. The purpose of this study was to confirm this finding using international data from 42% more collection sites and 25% more countries.

Methods

Data analyzed were from 71 prior and new collection sites in 40 countries at a wide range of latitudes. The analysis included 4876 patients with bipolar I disorder, 45% more data than previously analyzed. Of the patients, 1496 (30.7%) had a history of suicide attempt. Solar insolation data, the amount of the sun’s electromagnetic energy striking the surface of the earth, was obtained for each onset location (479 locations in 64 countries).

Results

This analysis confirmed the results of the exploratory study with the same best model and slightly better statistical significance. There was a significant inverse association between a history of suicide attempts and the ratio of mean winter insolation to mean summer insolation (mean winter insolation/mean summer insolation). This ratio is largest near the equator which has little change in solar insolation over the year, and smallest near the poles where the winter insolation is very small compared to the summer insolation. Other variables in the model associated with an increased risk of suicide attempts were a history of alcohol or substance abuse, female gender, and younger birth cohort. The winter/summer insolation ratio was also replaced with the ratio of minimum mean monthly insolation to the maximum mean monthly insolation to accommodate insolation patterns in the tropics, and nearly identical results were found. All estimated coefficients were significant at p < 0.01.

Conclusion

A large change in solar insolation, both between winter and summer and between the minimum and maximum monthly values, may increase the risk of suicide attempts in bipolar I disorder. With frequent circadian rhythm dysfunction and suicidal behavior in bipolar disorder, greater understanding of the optimal roles of daylight and electric lighting in circadian entrainment is needed.

Association between acute psychiatric bed availability in the Veterans Health Administration and veteran suicide risk: a retrospective cohort study

BACKGROUND

Veteran suicides have increased despite mental health investments by the Veterans Health Administration (VHA).

OBJECTIVE

To examine relationships between suicide and acute inpatient psychiatric bed occupancy and other community, hospital and patient factors.

METHODS

Retrospective cohort study using administrative and publicly available data for contextual community factors. The study sample included all veterans enrolled in VHA primary care in 2011-2016 associated with 111 VHA hospitals with acute inpatient psychiatric units. Acute psychiatric bed occupancy, as a measure of access to care, was the main exposure of interest and was categorised by quarter as per cent occupied using thresholds of ≤85%, 85.1%-90%, 90.1%-95% and >95%. Hospital-level analyses were conducted using generalised linear mixed models with random intercepts for hospital, modelling number of suicides by quarter with a negative binomial distribution.

RESULTS

From 2011 to 2016, the national incidence of suicide among enrolled veterans increased from 39.7 to 41.6 per 100 000 person-years. VHA psychiatric bed occupancy decreased from a mean of 68.2% (IQR 56.5%-82.2%) to 65.4% (IQR 53.9%-79.9%). VHA hospitals with the highest occupancy (>95%) in a quarter compared with ≤85% had an adjusted incident rate ratio (IRR) for suicide of 1.10 (95% CI 1.01 to 1.19); no increased risk was observed for 85.1%-90% (IRR 0.96; 95% CI 0.89 to 1.03) or 90.1%-95% (IRR 0.96; 95% CI 0.89 to 1.04) compared with ≤85% occupancy. Of hospital and community variables, suicide risk was not associated with number of VHA or non-VHA psychiatric beds or amount spent on community mental health. Suicide risk increased by age categories, seasons, geographic regions and over time.

CONCLUSIONS

High VHA hospital occupancy (>95%) was associated with a 10% increased suicide risk for veterans whereas absolute number of beds was not, suggesting occupancy is an important access measure. Future work should clarify optimal bed occupancy to meet acute psychiatric needs and ensure adequate bed distribution.

A longitudinal study of suicide and suicide attempt in northwest of Iran: incidence, predictors, and socioeconomic status and the role of sociocultural status

Background

A detailed community-level understanding of socioeconomic status (SES) and sociocultural status (SCS) of suicides and suicide attempters (SAs) in a prospective design could have significant implications for policymakers at the local prevention and treatment levels. The effect of SCS and SES on SAs is poorly understood and investigated in Iran. The present study aimed to investigate the incidence, trend, and role of SES and SCS on suicide and SAs.

Methods

A longitudinal study was conducted based on the registry for SAs in Malekan County, Iran, from 2015 to 2018. Demographic characteristics, SES, SCS, incidence rates, and predictors of suicidal behaviors were measured via structured instruments. Simple and multiple logistic regressions were used to estimate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

Results

A total of 853 SAs (32 suicides and 821 attempts) were identified during the study. Trend analysis revealed that the suicide rate significantly decreased from 2014 (10.28) to 2018 (1.75) per 100,000. In the final multiple variable models, age (26–40), male sex, unemployment, antisocial activities, history of SA, hanging method, and season (spring) increased the suicide risk while religious commitment had protective effects on suicide.

Conclusions

Our findings indicated that demographic characteristics, low SES, and SCS are associated with suicide. In this county, trend of suicide and SA were decreased from 2014 to 2018. This study findings highlight the need to consider a wide range of contextual variables, socio-demographic, SES, and SCS in suicide prevention strategies. Improving inter-sectoral collaborations and policymakers’ attitudes are imperative for SA reduction.

Experiences of Violence Among Individuals With Schizophrenia in Indonesia: A Phenomenological Study

Individuals with schizophrenia have a greater risk of violence compared to the general population. However, the contribution of schizophrenia to violence is heavily debated and remains unclear. The purpose of the current phenomenological study was to explore experiences of violence among individuals with schizophrenia (N = 40, mean age = 35.6 years) in West Java, Indonesia. A purposive sampling method was used to select participants from main referral hospitals. Focus group discussions were held, revealing two main themes-victimization by nurses and victimization by family-and eight sub-themes. Sub-themes for victimization by nurses included physical violence, verbal violence, restraint, neglected basic human needs, and no informed consent. Sub-themes for victimization by family were physical violence, verbal violence, and deception. Patients with schizophrenia have the same rights as all other patients, including the right to dignified treatment, the right to informed consent, and the right to patient safety. [Journal of Psychosocial Nursing and Mental Health Services, xx(x), xx-xx.].

Identification of socio-demographic, occupational, and societal factors for guiding suicide prevention: A cohort study of Swiss male workers (2000-2014)

INTRODUCTION

We modeled suicidal rate among Swiss working-age males, considering three groups of factors at socio-demographic, occupational, and societal levels jointly. Our goal was twofold: to verify the effect of occupation after adjustment for non-occupational factors and to identify protective and risk factors relevant for suicide prevention in working male adults.

METHODS

The study population included all men aged [18-65] years at the 2000 population census and followed up within the Swiss National Cohort (SNC). The risk of suicide was modeled using Poisson regression.

RESULTS

The cohort comprised 1,534,564 men and 4371 deaths by suicide. Suicide rate varied significantly according to age, civil status, nationality, highest education achieved, and socio-professional category at socio-demographic level; occupation, occupational activity branch, weekly working hours, and home-to-work commute time at occupational level; calendar period of death, region, religious affiliation, and volunteering activity at societal level. After adjustment for non-occupational factors, agricultural and fishery laborers, military and civil security workers, and health and social workers were identified as high-risk groups with respect to suicide.

CONCLUSION

This study evidenced a complex web of factors at socio-demographic, occupational, and societal levels behind the suicide in Swiss male workers and identified the most at-risk groups, deserving targeted prevention efforts.

Sunshine, temperature and suicidal behaviour in patients treated with antidepressants: an explorative nested case-control study

Our aim was to explore if different exposure windows for sunshine or temperature are associated with increased suicidal behaviour among people starting antidepressant treatment. 307 completed and 1674 attempted suicides were included as cases in the conditional logistic regression analyses, while controlling for potential confounders, including season, as well as temperature and hours of sunshine when these variables were not the main exposure variable. Ten controls were matched to each case using risk-set sampling. The role of season, age, and sex was examined with likelihood ratio tests (LRTs) with and without the respective interaction terms and with stratified analyses. There was no overall association between temperature or sunshine with suicidal behaviour. Age was a significant effect modifier for suicide and suicide attempt for both sunshine and temperature exposure. In stratified analyses, an increase of one degree Celsius in the average daily temperature during the last 4 weeks was associated, in the unadjusted model, with a 3% increase in the rate of suicide (p = 0.023) amongst older patients (65+). In the same age group, an increase of 1 h in the average daily sunshine during the last 4 weeks was associated with an 8% increase in the rate of suicide attempt (p = 0.002), while the respective increase for the exposure period of 5–8 weeks was 7% (p = 0.007). An increase of one degree Celsius in the average daily temperature during the last 4 weeks was associated with a 3% increase in the rate of suicide attempt (p = 0.007). These associations did not retain statistical significance in the adjusted models. No associations were found in the other age groups. Our results point to a possible effect modification by age, with higher risk of suicidal behavior associated with an increase in sunshine and temperature found in the older age groups.

High-lethality of suicide attempts associated with platelet to lymphocyte ratio and mean platelet volume in psychiatric inpatient setting

OBJECTIVES

A wide range of potential psychosocial, biological, genetic and environmental factors may interact with each other in determining suicidal behaviours. The aim of this study was to evaluate several biological parameters referred to the complete blood count values in 259 suicide attempters (SA) and 164 non-suicide attempters (control group), according to the lethality of suicidal behaviour.

METHODS

After attempting suicide, subjects were admitted to the emergency ward of the IRCCS Ospedale Policlinico San Martino and later to the section of Psychiatry from 1 January 2014 to 31 June 2019. Socio-demographic and clinical characteristics, as well as blood cells, were collected.

RESULTS

Individuals with high-lethality suicide attempts had a higher number of neutrophils, mean platelet volume, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and lower number of lymphocytes relative to both those with low-lethality suicide attempts and control group. After regression analysis, only the mean platelet volume and platelet to lymphocyte ratio resulted associated with a high-lethality suicide attempt (HLSA).

CONCLUSIONS

Our findings provide potential and useful peripheral biological markers able to help clinicians in understanding the complex phenomenon of suicide. However, further studies are needed to confirm the present findings.

Seasonal Trends in Hospitalization of Attempted Suicide and Self-Inflicted Injury in United States Adults

Introduction 

Suicide is the 10th leading cause of death in the United States (US) and the prevalence continues to increase. It is estimated that there is an average of 25 attempted suicides for every suicide death in the US, and the economic burden of suicide and attempted suicide is high. Identification of those at risk for suicide and attempted suicide can help with early and prompt intervention. Studies in Europe and Asia have shown that there is a relationship between seasonal patterns and suicidal risk. However, little is known about seasonal patterns of suicidal attempts in the US. Therefore, our study aimed to assess seasonal patterns by days of the week and months of the year in the US.

Methods

Hospitalized adult patients with suicide attempts and self-inflicted injury were identified using the discharge data from the National Inpatient Sample (NIS) from January 1, 2010 to December 31, 2014. We looked at the seasonal trends of patients with attempted suicide and self-inflicted injury by weekday vs weekend and month of the year over the five-year study period. We also assessed two groups, male and female with attempted suicide and compared trends and contributing risk factors over the study period using Student’s t-test and chi-square test.

Results

A total of 249,845 patients with attempted suicide and self-inflicted injury were reported during the study period with a prevalence rate increase of 15%, among which 70% were males, 65.5% white and 38.8% were age 40-64 years. An overall prevalence rate of about 168-200 per 100,000 hospitalizations was reported. There was a higher admission rate on weekends as compared to weekdays (190-300 vs 150-178 per 100,000 hospitalizations). Attempted suicide and self-inflicted injury admissions peaked during the months of July and August with a peak period range of 200-230 per 100,000 hospitalizations in a year.

Conclusion

The prevalence of attempted suicide is steadily rising. Awareness of the seasonal and epidemiological trends of attempted suicide and self-inflicted injury is a very important step towards developing effective strategies to prevent suicide and attempted suicide.

The effect of meteorological variables on suicide

We aimed to reveal the relationship between the meteorological variables and suicide rates (completed suicides and suicide attempts) independently of the seasonal cycle and holiday effects. This is an observational retrospective study. We collected the data on age, gender, and suicide method of all suicide cases transferred to hospitals from the scene by emergency medical services as well as those cases in which the victim died on the scene between January 1, 2017 and June 30, 2019. We also collected data on maximum, minimum, and average temperatures (°C), average humidity (%), and average actual pressure (hPa) measured daily in Ankara. The total number of cases due to suicide between the given dates was 6777. The suicide method in 60.1% of the cases was drug poisoning, which was the most common suicide method. Investigating the effect of meteorological variables on suicide cases (suicide attempts and completed suicides), the present study found that after smoothing the effect of the day of the week and seasonality, an increase in the minimum temperature on the day of the application by 1 unit (1°C degree) leads to an increase in the number of suicides by 0.01 point (0.01 ± 0.005, p = 0.046). There was no significant change in the variables other than the minimum temperature. We believe that the results of the present study will contribute to growing body literature about the epidemiology of suicide. We also believe that there is a need for large-scale studies that include individual data to reveal causality.

Light and Hormones in Seasonal Regulation of Reproduction and Mood

Organisms that inhabit the temperate zone exhibit various seasonal adaptive behaviors, including reproduction, hibernation, molting, and migration. Day length, known as photoperiod, is the most noise-free and widely used environmental cue that enables animals to anticipate the oncoming seasons and adapt their physiologies accordingly. Although less clear, some human traits also exhibit seasonality, such as birthrate, mood, cognitive brain responses, and various diseases. However, the molecular basis for human seasonality is poorly understood. Herein, we first review the underlying mechanisms of seasonal adaptive strategies of animals, including seasonal reproduction and stress responses during the breeding season. We then briefly summarize our recent discovery of signaling pathways involved in the winter depression-like phenotype in medaka fish. We believe that exploring the regulation of seasonal traits in animal models will provide insight into human seasonality and aid in the understanding of human diseases such as seasonal affective disorder (SAD).

An empirical investigation of the relationship between business performance and suicide in the US

Previous research suggests that mortality rates behave pro-cyclically with respect to economic growth, with suicides representing a notable exception that consistently increase in economic downturns. Over recent years, there is ample evidence in the literature that the working environment in the US has deteriorated significantly, suggesting that suicide rates may not necessarily behave in a counter-cyclical manner with business performance. Utilising recent suicide data, this study empirically tests the hypothesis that adverse working conditions over recent years may have resulted in a pro-cyclical relationship between business performance and suicide. Unlike previous studies, we use a stock market index, a leading macroeconomic indicator, to measure economic conditions from a business perspective. We employ the Autoregressive Distributed Lag (ARDL) co-integration methodology to study the long-run relationship between monthly S&P500 stock market data and age and gender-specific suicide rates during the period January 1999 to July 2017. Our results highlight substantial differences in age groups responses to fluctuations in business performance. We find a clear positive association between business performance and suicide rates for the youngest males and females aged 15-34 years, indicating that there is a human cost associated with improved business performance. Additionally, we investigate the association between economic insecurity, a unique aspect of the recent deterioration in the working environment, using the Implied Volatility Index "VIX" and age and gender-specific suicide rates. Our findings do not support a population-wide adverse impact of economic insecurity on suicide incidences. The exception was males aged 15-24, and females aged 55-64 for whom we find a significant positive association. Teaching work-life management and problem-solving skills to manage everyday work stressors may be important strategies to mitigate the psychological cost of business successes.

Seasonality of suicide: a multi-country multi-community observational study

AIMS

We aimed to investigate the heterogeneity of seasonal suicide patterns among multiple geographically, demographically and socioeconomically diverse populations.

METHODS

Weekly time-series data of suicide counts for 354 communities in 12 countries during 1986-2016 were analysed. Two-stage analysis was performed. In the first stage, a generalised linear model, including cyclic splines, was used to estimate seasonal patterns of suicide for each community. In the second stage, the community-specific seasonal patterns were combined for each country using meta-regression. In addition, the community-specific seasonal patterns were regressed onto community-level socioeconomic, demographic and environmental indicators using meta-regression.

RESULTS

We observed seasonal patterns in suicide, with the counts peaking in spring and declining to a trough in winter in most of the countries. However, the shape of seasonal patterns varied among countries from bimodal to unimodal seasonality. The amplitude of seasonal patterns (i.e. the peak/trough relative risk) also varied from 1.47 (95% confidence interval [CI]: 1.33-1.62) to 1.05 (95% CI: 1.01-1.1) among 12 countries. The subgroup difference in the seasonal pattern also varied over countries. In some countries, larger amplitude was shown for females and for the elderly population (≥65 years of age) than for males and for younger people, respectively. The subperiod difference also varied; some countries showed increasing seasonality while others showed a decrease or little change. Finally, the amplitude was larger for communities with colder climates, higher proportions of elderly people and lower unemployment rates (p-values < 0.05).

CONCLUSIONS

Despite the common features of a spring peak and a winter trough, seasonal suicide patterns were largely heterogeneous in shape, amplitude, subgroup differences and temporal changes among different populations, as influenced by climate, demographic and socioeconomic conditions. Our findings may help elucidate the underlying mechanisms of seasonal suicide patterns and aid in improving the design of population-specific suicide prevention programmes based on these patterns.